@JeanLouiseFinch -- I hope you will post the recipe you've tried when you have time, because my search brought up oodles of "Copycat Olive Garden Fettuccine Alfredo" recipes and all were different. About half used cream cheese, the other half didn't.
Here's one of them -- I have NOT tried it, but the name of the site sounds promising.
http://www.theslowroasteditalian.com/2014/02/olive-garden-copycat-alfredo-sauce-recipe.html
Olive Garden Copycat Alfredo Sauce
The decadent creamy Alfredo sauce from Olive Garden can now be enjoyed in your own home with this scrumptious copycat recipe loaded with cheese, cream and a special ingredient to really take it over the top. My family and I really enjoy the dishes at some of our favorite restaurants. However we do not love eating out. So, I take some of our favorite recipes and recreate them so we can enjoy them at home. Last time we polled our Facebook fans, our number 1 requested copycat was Olive Garden's Alfredo Sauce. Being one of Chad's favorites, we absolutely knew this needed to be our next copycat recipe that we brought you.
Alfredo sauce is a white cheese sauce made with Parmesan cheese. But this Olive Garden copycat is really done right with the addition of egg yolks to give it an incredible richness that will surprise your taste buds! With love from our kitchen table to yours! XO
Olive Garden Copycat Alfredo Sauce
2 cups half and half (or 1 cup milk and 1 cup heavy cream)
1 tablespoons unsalted butter
1 teaspoon garlic powder
½ cup fresh shredded Parmesan cheese
½ cup fresh shredded Romano cheese
4 large egg yolks
½ teaspoon kosher salt
½ teaspoon fresh ground black pepper (or white)
In a medium heat safe bowl, whisk egg yolks until lightened in color. Set aside.
Whisk together butter, garlic and half & half, bring to a simmer, in a medium saucepan over medium heat. Add cheeses and whisk to combine. Remove from heat.
Slowly pour 1 cup of cheese mixture into egg yolks, while whisking. Be careful to pour slowly and whisk while pouring to prevent the eggs from scrambling. Pour egg mixture back into saucepan over low heat and whisk until well combined. Add salt and pepper.
Remove from heat and allow to cool for 5 minutes. Alfredo sauce will thicken as it cools. Serve and enjoy!